1DSDOT(1) BLAS routine DSDOT(1)
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6 DSDOT - accumulation and result
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9 DOUBLE PRECISION FUNCTION DSDOT(N,SX,INCX,SY,INCY)
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11 INTEGER INCX,INCY,N
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13 REAL SX(*),SY(*)
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16 precision accumulation and result.
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18 Returns D.P. dot product accumulated in D.P., for S.P. SX and SY DSDOT
19 = sum for I = 0 to N-1 of SX(LX+I*INCX) * SY(LY+I*INCY), where LX = 1
20 if INCX .GE. 0, else LX = 1+(1-N)*INCX, and LY is defined in a similar
21 way using INCY.
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25 N (input) INTEGER
26 number of elements in input vector(s)
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28 SX (input) REAL array, dimension(N)
29 single precision vector with N elements
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31 INCX (input) INTEGER
32 storage spacing between elements of SX
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34 SY (input) REAL array, dimension(N)
35 single precision vector with N elements
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37 INCY (input) INTEGER
38 storage spacing between elements of SY
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40 DSDOT (output) DOUBLE PRECISION
41 DSDOT double precision dot product (zero if N.LE.0)
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44 REFERENCES
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46 C. L. Lawson, R. J. Hanson, D. R. Kincaid and F. T.
47 Krogh, Basic linear algebra subprograms for Fortran
48 usage, Algorithm No. 539, Transactions on Mathematical
49 Software 5, 3 (September 1979), pp. 308-323.
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51 REVISION HISTORY (YYMMDD)
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53 791001 DATE WRITTEN
54 890831 Modified array declarations. (WRB)
55 890831 REVISION DATE from Version 3.2
56 891214 Prologue converted to Version 4.0 format. (BAB)
57 920310 Corrected definition of LX in DESCRIPTION. (WRB) 920501
58 Reformatted the REFERENCES section. (WRB)
59 070118 Reformat to LAPACK style (JL)
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64BLAS routine November 2008 DSDOT(1)